Development of artifacts and symbols associated with Halloween formed over time encompassing customs of medieval holy days as well as contemporary cultures. The souling practice of commemorating the souls in purgatory with candle lanterns carved from turnips, became adapted into the making of jack-o'-lanterns. In traditional Celtic Halloween festivals, large turnips were hollowed out, carved with faces and placed in windows to ward off evil spirits. The carving of pumpkins is associated with Halloween in North America where pumpkins are both readily available and much larger – making them easier to carve than turnips. Many families that celebrate Halloween carve a pumpkin into a frightening or comical face and place it on their doorstep after dark. The American tradition of carving pumpkins preceded the Great Famine period of Irish immigration and was originally associated with harvest time in general, not becoming specifically associated with Halloween until the mid-to-late 1800s.
The imagery surrounding Halloween is largely a mix of the Halloween season itself, works of Gothic and horror literature, in particular the novels Frankenstein and Dracula, and nearly a century of work from American filmmakers and graphic artists, and British Hammer Horror productions, also a rather commercialized take on the dark and mysterious. Halloween imagery tends to involve death, evil, the occult, magic, or mythical monsters. Traditional characters include the Devil, the Grim Reaper, ghosts, ghouls, demons, witches, goblins, vampires, werewolves, zombies, skeletons, black cats, spiders, bats, and crows.
Particularly in America, symbolism is inspired by classic horror films (which contain fictional figures like Frankenstein's monster and The Mummy). Elements of the autumn season, such as pumpkins, corn husks, and scarecrows, are also prevalent. Homes are often decorated with these types of symbols around Halloween. Halloween costumes are traditionally those of monsters such as ghosts, skeletons, witches, and devils. They are said to be used to scare off demons. Costumes are also based on themes other than traditional horror, such as those of characters from television shows, movies, and other pop culture icons.
The colours black and orange are associated with the celebrations, perhaps because of the darkness of night and the colour of fire, autumn leaves, or pumpkins.